Also, for completeness, correct the listing of callee-save registers in callable return for x86 & x86_64. original commit: 4cd942be6ab2eb5e02f6d6c5c509db3131bd015f
7.ss, scheme.1.in, comments of many files original commit: 06f858f9a505b9d6fb6ca1ac97234927cb2dc641
original commit: 47a210c15c63ba9677852269447bd2f2598b51fe